Ambient air pollution, especially fine particulate matter, is one of the significant public health concerns in countries like China. While short-term exposure to fine particulate matter is associated with increased risk of stroke, long-term exposure is limited. The objective of this research is to study the effect of long-term exposure of fine particulate matter on the incidence of stroke.

This is a population-based cohort study carried out across 15 provinces across China. The participants included 117,575 Chinese men and women without stroke at baseline. The PM2.5 level from 2000 to 2015 at the participants’ residential addresses was 31.2 μg/m3 to 97.0 μg/m3. The primary outcome pleasures of the research were the incidence of the total, ischemic, and hemorrhagic stroke.

During the follow-up of 900,214 person-years, 3,540 cases of incident stroke were recognized, out which2230 were ischemic, and 973 were hemorrhagic. For an increase in every 10 μg/m3 in PM2.5 concentration, the risk of incident stroke increased by 13% (incident stroke), 20% (ischemic stroke), and 12% (hemorrhagic stroke).

The study concluded that long-term exposure to fine particulate matter at high concentrations is directly associated with incident stroke and its major subtypes. These findings indicate that an increase in air pollution puts the entire population at risk of stroke.

Ref: https://www.bmj.com/content/367/bmj.l6720

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